Continuous fiber inserts for injection molded parts

Abstract

A process for incorporating continuous graphite fiber reinforcement impregnated with polyamide-imide polymer onto injection molded polyamide-imide parts. These impregnated parts are useful as automotive parts such as push rods or rocker arms, and for aircraft parts such as fittings and secondary structural parts.

I claim: 
     
       1. A molded object comprising the following structure: ##STR4## and units of: ##STR5## wherein one carbonyl group is meta to and one carbonyl group is para to each amide group and wherein z is a trivalent benzene ring or lower-alkyl-substituted trivalent benzene ring, R 1  and R 2  are different and are divalent aromatic hydrocarbon radicals of from 6 to about 10 carbon atoms or two divalent aromatic hydrocarbon radicals of from 6 to about 10 carbon atoms joined directly or by stable linkages selected from the group consisting of --O--, methylene, --CO--, --SO 2  --, and --S-- radicals and wherein said R 1  and R 2  containing units run from about 10 mole percent R 1  containing unit and about 90 mole percent R 2  containing unit to about 90 mole percent R 1  containing unit and about 10 mole percent R 2  containing unit coated with continuous graphite fiber or woven graphite fabric or graphite unidirectional tape impregnated with a polyamide-imide of the following structure: ##STR6## and units of: ##STR7## wherein the free carboxyl groups are ortho to one amide group, Z is a trivalent benzene ring or lower-alkyl-substituted trivalent benzene ring, R 1  and R 2  are the same or are different and are divalent aromatic hydrocarbon radicals of from 6 to about 10 carbon atoms or two divalent aromatic hydrocarbon radicals of from 6 to about 10 carbon atoms joined directly or by stable linkages selected from the group consisting of --O--, methylene, --CO--, --SO 2  --, and --S-- radicals and wherein said R 1  and R 2  containing units run from about 10 mole percent R 1  containing unit and about 90 mole percent R 2  containing unit to about 90 mole percent R 1  containing unit and about 10 mole percent R 2  containing unit. 
     
     
       2. The molded object of claim 1 wherein, in both the molded object and the polyamide-imide impregnated continuous graphite fiber, or woven graphite fabric or graphite unidirectional tape, R 1  is: ##STR8## and R 2  is: ##STR9## or wherein R 1  is: ##STR10## and R 2  is: ##STR11## 
     
     
       3. The molded object of claim 1, wherein in both the molded object and the graphite woven polyamide-imide coated fabric, Z is a trivalent benzene ring, R 1  is: ##STR12## and R 2  is: ##STR13## and wherein the concentration range runs from about 30 mole percent of the R 1  containing units and about 70 mole percent of the R 2  containing units to about 70 mole percent of the R 1  containing units and about 30 mole percent of the R 2  containing units. 
     
     
       4. A molded object comprising the following structure: ##STR14## and units of: ##STR15## wherein one carbonyl group is meta to and one carbonyl group is para to each amide group and wherein Z is a trivalent benzene ring or lower-alkyl-substituted trivalent benzene ring, R 1  and R 2  are different and are divalent aromatic hydrocarbon radicals of from 6 to about 10 carbon atoms or two divalent aromatic hydrocarbon radicals of from 6 to about 10 carbon atoms joined directly or by stable linkages selected from the group consisting of --O--, methylene, --CO--, --SO 2  --, and --S-- radicals and wherein said R 1  and R 2  containing units run from about 10 mole percent R 1  containing unit and about 90 mole percent R 2  containing unit to about 90 mole percent R 1  containing unit and about 10 mole percent R 2  containing unit coated with a graphite fabric impregnated with a polyamide-imide of the following structure: ##STR16## and units of: ##STR17## wherein one carbonyl group is meta to and one carbonyl group is para to each amide group and wherein Z is a trivalent benzene ring or lower-alkyl-substituted trivalent benzene ring, R 1  and R 2  are different and are divalent aromatic hydrocarbon radicals of from 6 to about 10 carbon atoms or two divalent aromatic hydrocarbon radicals of from 6 to about 10 carbon atoms joined directly or by stable linkages selected from the group consisting of --O--, methylene, --CO--, --SO 2  --, and --S-- radicals and wherein said R 1  and R 2  containing units run from about 10 mole percent R 1  containing unit and about 90 mole percent R 2  containing unit to about 90 mole percent R 1  containing unit and about 10 mole percent R 2  containing unit. 
     
     
       5. The molded object of claim 4 wherein, in both the molded object and the graphite woven polyamide-imide coated fabric, R 1  is: ##STR18## and R 2  is: ##STR19## or wherein R 1  is: ##STR20## and R 2  is: ##STR21## 
     
     
       6. The molded object of claim 4 wherein, in both the molded object and the graphite woven polyamide-imide coated fabric, Z is a trivalent benzene ring, R 1  is: ##STR22## and R 2  is: ##STR23## and wherein the concentration range runs from about 30 mole percent of the R 1  containing units and about 70 mole percent of the R 2  containing units to about 70 mole percent of the R 1  containing units and about 30 mole percent of the R 2  containing units. 
     
     
       7. A process for injection molding continuous woven graphite fibers or graphite woven fabrics or graphite unidirectional tape impregnated with a polyamide-imide of claim 1 on the surface of polyamide-imides of the following structures: ##STR24## and units of: ##STR25## wherein one carbonyl group is meta to and one carbonyl group is para to each amide group and wherein Z is a trivalent benzene ring or lower-alkyl-substituted trivalent benzene ring, R 1  and R 2  are different and are divalent aromatic hydrocarbon radicals of from 6 to about 10 carbon atoms or two divalent aromatic hydrocarbon radicals of from 6 to about 10 carbon atoms joined directly or by stable linkages selected from the group consisting of --O--, methylene, --CO--, --SO 2  --, and --S-- radicals and wherein said R 1  and R 2  containing units run from about 10 mole percent R 1  containing unit and about 90 mole percent R 2  containing unit to about 90 mole percent R 1  containing unit and about 10 mole percent R 2  containing unit, which process comprises injecting into the mold cavity the impregnated fabric and then injection molding the polyamide-imide copolymer at a temperature of about 630° to about 680° F. at a back pressure of about 50 to about 5000 psi. 
     
     
       8. The process of claim 7 wherein, in both the molded object and the graphite woven polyamide-imide coated fabric, R 1  is: ##STR26## and R 2  is: ##STR27## or wherein R 1  is: ##STR28## and R 2  is: ##STR29## 
     
     
       9. The process of claim 7 wherein, in both the molded object and the graphite woven polyamide-imide coated fabric, Z is a trivalent benzene ring, R 1  is: ##STR30## and R 2  is: ##STR31## and wherein the concentration range runs from about 30 mole percent of the R 1  containing units and about 70 mole percent of the R 2  containing units to about 70 mole percent of the R 1  containing units and about 30 mole percent of the R 2  containing units.